In 2014, the U.S. Surgeon General issued a Call to Action to Prevent Skin Cancer. For over two decades, the National Cancer Institute has funded research on community-based skin cancer prevention interventions. While research has identified successful interventions in some domains, gaps still exist and there are opportunities to expand the research and practice beyond existing approaches. Starting in 2010, researchers and practitioners worldwide have met approximately every two years to exchange the latest research and share community-based efforts on primary and secondary prevention of skin cancer. The 1st International Conference on UV and Skin Cancer Prevention was held in Copenhagen hosted by the Danish Cancer Society and TrygFonden. The 2nd International Conference was hosted by the European Skin Cancer Foundation in Berlin in 2013 and the 3rd International Conference, by the Cancer Council Victoria in Melbourne in 2015. This application requests support for the 4th International Conference on UV and Skin Cancer Prevention to be held in North America in Toronto, Canada on May 1-4, 2018. The conference objective is to convene international experts in skin cancer prevention to advance prevention efforts through collaboration and development of new directions in research and practice. The specific aims are: 1) To expand perspectives and create new collaborative opportunities in skin cancer prevention through the provision of cross-cutting plenary sessions that engage experts from outside of traditional skin cancer prevention disciplines with skin cancer prevention researchers and practitioners; 2) to provide a space to discuss innovative approaches and research methodologies, such as the use of new measurement and analysis techniques (e.g., geo-spatial modeling and analysis of big data); 3) to advance communication about skin cancer prevention among clinicians, behavioral scientists, and practitioners, 4) to offer opportunities for new skin cancer researchers to present their work to an international audience and 5) to report the consensus, state-of-the-art, and new directions of the conference in an academic journal. An Organizing Committee, Co-Chaired by Dr. David Buller from Klein Buendel, Inc. (PI on this application) and Mr. George Kapelos from Ryerson University, is planning the conference. The conference will be held on the campus of Ryerson University. The scientific program will contain keynote, plenary, concurrent, and poster sessions. The Canadian Dermatology Association is a sponsor the 4th International Conference, providing financial support. The Centers for Disease Control and Prevention will provide in-kind support. The Organizing Committee is soliciting support from the World Health Organization and American and Canadian agencies, foundations, and research centers with an interest in skin cancer prevention. The 4th International Conference is expected to attract 250 paid attendees comprised of behavioral scientists, epidemiologists, radiation scientists, policy makers, public health advocates and practitioners, cancer biologists, general practitioners, dermatologists, and related clinicians.